According
to the Orkneyinga Saga, Orkney's conversion
to Christianity was achieved in a particularly dramatic fashion.

The tale centres around Olaf Trygvesson, a rich,
popular and successful Viking leader, who had been campaigning throughout
Britain for several years.

In 995, one year after he had been converted
to Christianity himself, Olaf was heading back to Norway with the
intention of making a bid for the Norwegian throne.

Leaving Ireland, "Olaf sailed east with five
ships and didn't break his journey until he reached Orkney"

In Orkney, he came across Earl Sigurd preparing for a raiding expedition
at Osmundwall - the place now known as Kirk Hope, in Walls.

The saga recounts:

"Olaf sent a messenger
to him, asking Sigurd to come over to his ship as he wanted a
word with him.

'I want you and all your subjects
to be baptised,' he said when they met.

'If you refuse, I'll have
you killed on the spot, and I swear that I'll ravage every island
with fire and steel.'

The Earl could see what kind of
situation he was in and surrendered himself into Olaf's hands.
He was baptised and Olaf took his son, called Hvelp or Hundi,
as a hostage and had him baptised too under the name of Hlodvir.
After that, all Orkney embraced the faith. Olaf sailed east to
Norway taking Hlodvir with him, but Hlodvir didn't Live long and
after his death Sigurd refused to pay homage to King Olaf."The
Orkneyinga Saga Ch 12

The saga does not mention whether Sigurd renounced
Christianity after the death of his son, but the accounts of his
spectacular later exploits, and death, certainly imply that he remained
true to his pagan beliefs.